Parsing inflected forms may not always work as expected. If the following does not give the correct word, try Latin Words or Perseus.
illactĕnus, adv., v. illatenus.
illātĕnus or illactĕnus, adv. [illetenus], so far (post-class. and very rare): navitas precum ejus (Arionis) commiseritum esse illactenus, ut, etc., Gell. 16, 19, 11: litteras illatenus, qua dixi, legendas praebebat, App. Mag. p. 326; cf. Fronto Ter. Als. 4.